Excitatory actions of substance P in the rat lateral posterior nucleus.
Excitatory actions of substance P in the rat lateral posterior nucleus.
复制标题
P物质对大鼠外侧后核的兴奋作用。
DOI：
10.1111/j.1460-9568.2009.07035.x
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
Cox,CharlesL
中科院分区：
文献类型：
--
作者：
Paul,Kush;Cox,CharlesL
侧后核（LP）接收来自新皮层和上丘（SC）的输入，并参与高级视觉信息的整合和处理。LP中的中继神经元含有速激肽受体，并由含有P物质（SP）的SC神经元和视觉皮层的V层神经元支配。在这项研究中，我们使用全细胞记录技术研究了SP对LP中继神经元的作用。SP在LP神经元沿LP核侧细分（LPl）的背-尾侧范围产生了渐变的去极化反应，与尾侧LPl神经元相比，吻侧LPl神经元的反应明显更大。在吻侧LPl中，SP （5-2000 nm）以浓度依赖的方式去极化几乎所有被测的中继神经元（> 98%）。电压箝位实验表明，SP产生与电导降低相关的内向电流。内向电流主要由神经激肽受体（NK）1速激肽受体介导，尽管特异性nk2和nk3受体激动剂可产生明显较小的内向电流。选择性nk1受体拮抗剂RP67580对SP介导应答的抑制作用为71.5%，且显著大于nk2和nk3受体拮抗剂GR159897和SB222200对SP应答的抑制作用。SP介导的响应表现出与K+电导一致的电压特性，并被K+通道阻滞剂Cs+衰减。我们的数据表明，SP可能调节LPl中正在处理和整合的视觉信息，这些信息来自于collcoller来源的输入。
The lateral posterior nucleus (LP) receives inputs from both neocortex and superior colliculus (SC), and is involved with integration and processing of higher‐level visual information. Relay neurons in LP contain tachykinin receptors and are innervated by substance P (SP)‐containing SC neurons and by layer V neurons of the visual cortex. In this study, we investigated the actions of SP on LP relay neurons using whole‐cell recording techniques. SP produced a graded depolarizing response in LP neurons along the rostro‐caudal extent of the lateral subdivision of LP nuclei (LPl), with a significantly larger response in rostral LPl neurons compared with caudal LPl neurons. In rostral LPl, SP (5–2000 nm) depolarized nearly all relay neurons tested (> 98%) in a concentration‐dependent manner. Voltage‐clamp experiments revealed that SP produced an inward current associated with a decreased conductance. The inward current was mediated primarily by neurokinin receptor (NK)1tachykinin receptors, although significantly smaller inward currents were produced by specific NK2and NK3receptor agonists. The selective NK1receptor antagonist RP67580 attenuated the SP‐mediated response by 71.5% and was significantly larger than the attenuation of the SP response obtained by NK2and NK3receptor antagonists, GR159897 and SB222200, respectively. The SP‐mediated response showed voltage characteristics consistent with a K+conductance, and was attenuated by Cs+, a K+channel blocker. Our data suggest that SP may modulate visual information that is being processed and integrated in the LPl with inputs from collicular sources.